1. Technical Field
The present invention relates generally to automatically controlled matrix switching systems and, more particularly, to methods and apparatus for automatically and selectively providing cross-connect switching functions in a telephone system.
2. Discussion of the Prior Art
In the above-noted U.S. patent application Ser. No. 08/111,770, there is described and illustrated a remotely controlled cross-connect matrix arrangement having particular but not limited application in selectively connecting multiple telephone subscriber pairs to multiple telephone system or central office lines. That system utilizes a unique pick and place mechanism for automatically inserting jumper pins at desired matrix locations to provide service for individual subscribers. Although that pick and place mechanism is effective to perform its intended functions, the mechanism requires three separate motors to position the jumper pin holder along three respective axes to insert and/or remove a jumper pin. The three motor approach is costly and results in a degree of complexity that has now been found to be unnecessary.
It has also been found that the cross-connect matrix approach of the above-referenced prior patent application is ideally suited for performing other important telephone system functions. In particular, telephone facilities that are typically utilized in providing telephone service to a customer include a telephone number, a central office line termination, a cross-connection via a mainframe or cross-connection unit to a cable pair extending via several types of outside plant facilities to a terminal near the customer's home or business, and wiring from the terminal into the home/business and to the telephone. Each of these components must have its own identification code to distinguish it from among thousands of identical components that may or may not be in service. These codes for the various components are specified on a service installation order to inform technicians exactly which components to connect together to provide the overall circuit for the customer. When all of the components have been properly connected and the line tested, the customer can plug his/her telephone into the line and utilize the service.
Telephone companies typically issue orders to disconnect each of these facility connections all along the circuit when a customer moves or the service is otherwise disconnected. Individual components are then returned to the assignment availability list for re-use in response to a subsequent request for service. In recent years, increases in technical labor costs have caused telephone companies to attempt a variety of schemes to reduce that cost by leaving many of the component connections intact when a customer disconnects service, and then using the same connected components for the next customer to occupy the former customer's premises. This method of operation is known by various names throughout the industry such as:
(a) Dedicated Outside Plant (DOP). In this approach the cable pair remains connected from the mainframe in the central office to the serving area interface (i.e., the cross-connection point), to a terminal at the customer's location and on into the home/business. This technique is sometimes called "connect-thru". PA1 (b) Dedicated Inside Plant (DIP). The office equipment line termination remains connected to the cable pair that served the former customer. PA1 (c) Flow Through. This term is used when service is established for a new customer by reusing all former facilities and no field work or central office work is required. PA1 (d) Soft Dial Tone. This is a recent innovation made possible by stored program controlled switching systems permitting programming of the office equipment terminal that had been used by the previous occupant in a manner to permit the incoming new customer to contact only the telephone business office and emergency 911 even though service has not been officially established at the facility.
All of the foregoing methods require that the facilities to the customer's location be left in place from the customer's connection block in the home/business to the office equipment terminal in the central office. There are tremendous labor savings inherent in these methods of operation. However, as telephone companies have become involved in these processes they have found that there are serious drawbacks and problems not readily apparent in initial plans. Some of these, for the above-described methods include:
1. Dedicated Outside Plant (DOP). The greatest obstacle in DOP is loss of flexibility in utilizing capital investment. Outside plant cable facilities are designed using a multiplying scheme to provide maximum flexibility in utilizing cable pairs. When these pairs are left connected to the central office mainframe, they are unavailable for changes and rearrangements necessary to fully utilize capital investment. The result is an increase in capital requirements for new facilities. A feeder cable pair from a serving area interface to the central office is very expensive; when dedicated to a non-working line, it is not available for use by paying customers, resulting in a waste of capital investment.
2. Dedicated Inside Plant (DIP). There is a tremendous capital penalty involved in leaving the central office equipment connected to the outside cable pair. Central office administrative spares (i.e., operating spares) are designed and provided from specific formulae based on a precise percentage of available lines being idle at any given time. When these office equipment terminals are left connected to the outside plant cable pair, they are unavailable for use as administrative spares and can be assigned only when a customer occupies the dwelling or business where the cable pair is terminated. At any given time there are approximately ten percent of the available lines idle or disconnected in the normal course of business (i.e., people moving in and out of the city, people moving from one home or business to another, new customers, present customers disconnecting service, customers adding lines, etc.). This activity is called "the float" or "churn" in the telephone industry. It is an expensive but necessary part of the telephone business. The average central office line termination currently costs approximately one hundred and fifteen dollars to one hundred and fifty dollars each. When one considers the thousands of lines involved in the DIP method, it becomes apparent that this method is very expensive from a capital utilization point of view. Considerable effort has been expended throughout the industry to resolve the labor versus capital costs impasse. Many companies have indicated that the economic impact of idle capital investment, while having to purchase new terminations for new service, outweighs the cost of making the connections manually.
3. Flow Through. When a decision to stop or not provide DIP is implemented, the "flow through" of service orders is stopped. This, in effect, puts the service order process back where it was before the labor saving plans were implemented, meaning that every service order must be manually processed to establish service. When one considers all the different assignments and cross-connections involved, this obviously is a major problem. Even with fully dedicated outside plant (DOP) and inside plant (DIP), there is another serious obstacle to increasing the labor saving "flow through" of service orders to establish telephone service. This is the problem of identification of the line serving the customer that is just moving in to occupy the premises. Many homes, particularly in rural areas, do not have precise addresses. Many apartment buildings do not precisely identify the apartment location; rather, only the street address of the apartment building is listed, and some carry only the street address plus the floor or story number. Thus, even if such a customer is properly connected through to the central office equipment, the customer has no way of telling the business office that service is desired, or precisely where he/she lives, or what facility is connected to the dwelling unit. In theory, these data should be available from assignment records; however, if the addresses are not available, assignment records cannot locate the customer. In many cases, entire duplicate facility connections are assigned and sent to the field for the technician to install because the original facility records cannot be located. In order to solve a part of this problem, that is, notification to the business office that service is desired, the "soft dial tone" technique was developed.
4. Soft Dial Tone. Many telephone companies found that simply leaving facilities connected to the main frame still required the customer to find a working telephone or pay telephone to call the business office to apply for service. The "Soft Dial Tone" technique was developed to solve this problem. Under this technique, all facilities are left connected from the customer to the switching machine. In addition, a telephone number is assigned and attached to the non-working line. This switching machine, as do all switching machines, has means to automatically identify the telephone number that is attached to a particular telephone facility. This is called "Automatic Number Identification" (ANI). The "soft dial tone" operation under this method proceeds in the following manner. When a customer moves into a dwelling unit that has been left connected through to the central office switch, he/she plugs in a telephone and receives a dial tone. The telephone number assigned to that facility has been programmed in the switch software to restrict all calls from that number except 911 or to the telephone company business office number. When the customer calls the business office, assuming everything has been perfectly recorded and all facilities have been properly connected, the customer gives the business office the address of the dwelling unit. The service representative then calls an assignment bureau where all facilities are recorded and associated with the dwelling units, and gives the assignor the house address of the applicant. Assuming again that the customer can provide the exact address, apartment location, street numbers etc., the assignor can determine from the records the probable cable facility that the customer has called in on. He/she then has frame technicians "pull an ANI" on the cable pair to find the telephone number that is connected to that pair. If the ANI number matches the number in the records, the business office informs the customer that service will be established that day. Service orders are then issued to establish service using the facilities for that dwelling unit; in addition, the temporary telephone number will have to be changed or reprogrammed in the switching machine to permit normal service. If all goes well and every piece of the facility was left as the records indicated, the service is established. Obviously this is better than the old method of simply leaving the cable pairs connected to the central office mainframe, as the old method adds additional labor back into the cost of providing the service. It is totally dependent, however, upon records and data that are notoriously inaccurate and, it requires coordination between four disparate work groups. These groups are not co-located and may even be in different cities. In addition, fully dedicated facilities for soft dial tone require the addition of another large capital investment to add a telephone number to a non-working line that produces no revenue. The capital cost of a single telephone number has been estimated between $300-$500. When one considers the thousands of lines that must be treated in this fashion every day of the year, the capital requirements are obvious. Studies have shown that the capital cost of the facilities and telephone numbers involved, exceed the value of labor saved by use of this technique.
The foregoing description is applicable approximately twenty five percent of the time when dedicated facilities are utilized in both DIP and DOP techniques. Obviously, the "flow through" percentage is zero for non-dedicated facilities. It must be recognized that the process takes place every working day of the year in every central office in cities and towns all over the world. The expense and labor involved in these processes are enormous, and great amounts of thought, study and effort are expended in attempting to overcome specific obstacles and problems to establishing "flow through" of orders for telephone service. These problems include: idle outside plant capital investment resulting from dedicated outside plant cable pairs; idle and "trapped investment" of central office line terminations when DIP is used; and the inability to efficiently establish same day service when dedicated facilities are not utilized. In many cases the calling customer does not know the exact address or even the apartment number.
Where telephone numbers are not assigned to non-working lines because of the high capital expense, there is no ANI capability and therefore the assignment force is unable to identify the calling line even when the exact address is known and given to the business office. Without a telephone number, no electronic tests of the facility can be made to assure proper operation because all electronic test equipment connects to the facility through the telephone number. This means that service must first be established, and then operational testing can be done. In many cases the facility is not suitable and all work must be done again and service activation is delayed.
The present invention solves these and other telephone service activation problems and inefficiencies at a great capital and labor savings to the telephone company. In addition, customer service is greatly improved.